diff options
| -rw-r--r-- | kernel/trace/ftrace.c | 93 |
1 files changed, 93 insertions, 0 deletions
diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c index bfdbce78064b..f1ccf8be9df7 100644 --- a/kernel/trace/ftrace.c +++ b/kernel/trace/ftrace.c @@ -3969,6 +3969,97 @@ static int cache_mod(struct trace_array *tr, return ret; } +static int +ftrace_set_regex(struct ftrace_ops *ops, unsigned char *buf, int len, + int reset, int enable); + +static void process_mod_list(struct list_head *head, struct ftrace_ops *ops, + char *mod, bool enable) +{ + struct ftrace_mod_load *ftrace_mod, *n; + struct ftrace_hash **orig_hash, *new_hash; + LIST_HEAD(process_mods); + char *func; + int ret; + + mutex_lock(&ops->func_hash->regex_lock); + + if (enable) + orig_hash = &ops->func_hash->filter_hash; + else + orig_hash = &ops->func_hash->notrace_hash; + + new_hash = alloc_and_copy_ftrace_hash(FTRACE_HASH_DEFAULT_BITS, + *orig_hash); + if (!new_hash) + return; /* Warn? */ + + mutex_lock(&ftrace_lock); + + list_for_each_entry_safe(ftrace_mod, n, head, list) { + + if (strcmp(ftrace_mod->module, mod) != 0) + continue; + + if (ftrace_mod->func) + func = kstrdup(ftrace_mod->func, GFP_KERNEL); + else + func = kstrdup("*", GFP_KERNEL); + + if (!func) /* warn? */ + continue; + + list_del(&ftrace_mod->list); + list_add(&ftrace_mod->list, &process_mods); + + /* Use the newly allocated func, as it may be "*" */ + kfree(ftrace_mod->func); + ftrace_mod->func = func; + } + + mutex_unlock(&ftrace_lock); + + list_for_each_entry_safe(ftrace_mod, n, &process_mods, list) { + + func = ftrace_mod->func; + + /* Grabs ftrace_lock, which is why we have this extra step */ + match_records(new_hash, func, strlen(func), mod); + free_ftrace_mod(ftrace_mod); + } + + mutex_lock(&ftrace_lock); + + ret = ftrace_hash_move_and_update_ops(ops, orig_hash, + new_hash, enable); + mutex_unlock(&ftrace_lock); + + mutex_unlock(&ops->func_hash->regex_lock); + + free_ftrace_hash(new_hash); +} + +static void process_cached_mods(const char *mod_name) +{ + struct trace_array *tr; + char *mod; + + mod = kstrdup(mod_name, GFP_KERNEL); + if (!mod) + return; + + mutex_lock(&trace_types_lock); + list_for_each_entry(tr, &ftrace_trace_arrays, list) { + if (!list_empty(&tr->mod_trace)) + process_mod_list(&tr->mod_trace, tr->ops, mod, true); + if (!list_empty(&tr->mod_notrace)) + process_mod_list(&tr->mod_notrace, tr->ops, mod, false); + } + mutex_unlock(&trace_types_lock); + + kfree(mod); +} + /* * We register the module command as a template to show others how * to register the a command as well. @@ -5682,6 +5773,8 @@ void ftrace_module_enable(struct module *mod) out_unlock: mutex_unlock(&ftrace_lock); + + process_cached_mods(mod->name); } void ftrace_module_init(struct module *mod) |